1. Field of the Invention
This application relates generally to a method and apparatus for preparing a drug or medicinal substance and, more specifically, to method and apparatus for selecting a specific preparation that may include reconstituting, diluting, measuring and mixing a drug or medicinal substance, and displaying preparation instructions and preparing a label including content related to the preparation and optionally encoding relevant preparation information as a machine-readable code.
2. Description of Related Art
It is common for drugs or other medicinal substances to require one or more preparation steps prior to being administered to patients at a healthcare facility. The preparation steps may include, but are not limited to: reconstitution; dilution; measuring a specific amount of a drug and/or substance; mixing multiple drugs and/or substances; packaging the final preparation in an appropriate container for delivery; and labeling the container with information related to the drugs and/or substances and/or preparation steps applied.
A specific drug preparation often begins with a prescription from a physician. This prescription may by issued verbally, or handwritten, or submitted using an electronic system.
A prescribing physician will often specify a dose and volume of the drug to be administered. To prepare a drug with the dose and volume prescribed, a clinician will select one or more originating drug containers having a proper starting concentration with the required amount of the specified drug. The number of containers, starting concentration and the amount of drug required from the containers may be specified as part of the drug recipe or preparation instructions that is associated with the specific preparation. In some cases, the contents of the originating drug containers must be diluted to achieve the prescribed dose and volume. A clinician preparing a diluted drug must select an appropriate diluent for diluting the drug, then calculate the volume of the drug and the volume of the diluent to be combined to achieve the desired dose and volume requested by the prescriber. This information can be included as part of the drug recipe to reduce the number a calculations a clinician must perform during the preparation process. The final drug preparation is commonly administered to a patient via a syringe or other delivery container.
Drugs are typically expensive, and are often administered in many different doses and volumes at a given healthcare facility depending on the specific needs of each patient. It is impractical to inventory, in a pharmacy, originating drug containers storing each of the different concentration variants that may be required.
Instead, a reasonable number vials storing the drug at different starting concentrations will commonly be kept in an inventory, from which the prescribed dose and volume and special concentrations are prepared. However, the dilution procedure described above for preparing a dilution is complex and time consuming. Additionally, the calculations of the drug volume and diluent volume to be combined to fulfill the prescription are prone to human error, thereby raising the possibility that a dilution with the improper dose and volume may be prepared.